Among ignorance (al-jahl), there’s that which is simple (basīṭ), which is merely the absence of knowledge ( ͑adam al- ͑ilm) in the soul. […]. And among ignorance, there’s that which is composite (murakkab), and it is not merely an absence; rather, there’s in it, together with the absence of knowledge, the existence of an opinion that is contrary (muḍād) to it, and it is ignorance by way of possession (qunya) and habit (malaka). […]. And this is only called ‘compound’ ignorance because there’s in it a conflict (khilāf) [with] knowledge and an opposition to it in two respects: the first is that the soul is devoid of knowledge, and the second is that, with its emptiness of knowledge, there has occurred in it the contrary (ḍidd) of knowledge.

Know that knowledge (al- ͑ilm) is [1] sometimes applied and by it is meant the occurrence of the form of a thing in the intellect. It is divided [1.1] into bare conceptualization (taṣawwurmuṭlaq) – like our conception ‘the sun’, and ‘the moon, and ‘the intellect’ – and [1.2] into conceptualization with assent (taṣdīq) – like knowing that the world is temporally originated (muḥdath). Assent is a judgment, by negation or affirmation, between two things. And [2] other times [knowledge] is applied and by it is meant certainty (al-yaqīn), and is [as such] a division of assent because it is an assent qualified by jazm, thubāt, and muṭābaqa. [As such] it is not divided into conceptualization and assent that is firmly convinced (jāzim), corresponds (muṭābiq), and justified (thābit); for a thing is not divided into itself and into something different from itself.

Suppose some x comes into existence at t, persists for a while, and then ceases to exist. Question is: can x ‘return’ (yu’ād) to existence, say at t’? Assume that sort of thing can happen. If so, then t would also have to return to existence alongside x, insofar as it is a part of what individuates x as x. But in that case, t and t’ would be identical; and therefore, x’s return to existence would be the same thing as its beginning of existence. But that’s clearly a contradiction. And thus, the initial assumption is necessarily false.